The present invention relates to a method of manufacturing a thin copper plate with at least one flow conduit parallel to its plane.
In heat exchangers and the like, it is desirable to obtain a maximal surface area of the plate which yields or receives heat. At the same time, it is desirable to obtain maximum conduction of heat from the heat exchanger fluid to the flanges or ribs which increase the surface area. It is known that copper and its alloys are the best heat conductors in technical applications, and for this reason they are used whenever financially possible. Rib tubes made of copper in boilers, and automobile radiators made of copper alloys, are examples of applications in which copper metals have proved their superiority over other metals. The advantageous properties of copper also include its high resistance to corrosion in comparison with aluminum, for example.
When it is necessary either to heat or to cool large surfaces, the fixing of tubes for conveying fluids to the surfaces in question complicates the use of copper metals. In such cases the fluid-conveying tubes are fixed to the plates either by welding or by bracing, whereby the construction becomes expensive and the conduction of heat from the fluid to the plate is reduced owing to the small contact surface and the solder. In these cases the plates are often made of aluminum, and then the required fluid tubes can be made by fitting graphite in the area of the desired flow conduits between the two aluminum plates and by joining the aluminum plates by hot working, whereafter the flow conduits are opened by using pressure. Owing to the high hot-working temperature, such a method is impossible with copper metals and would in practice be very expensive.
The object of the present invention is thus to produce a simpler and less expensive method than previously for producing a thin copper plate with flow conduits parallel to its plane. When necessary, separate inner tubes can be installed in the opened tubular conduits to improve corrosion resistance or for some other practical reason.